Cardiology Flashcards
Define AAA.
A localised enlargement of the abdominal aorta such that the diameter is > 3 cm or > 50% larger than normal diameter.
What is the normal diameter of an aorta?
2 cm
What are the risk factors for AAA?
Severe atherosclerotic damage to aortic wall
Family history
Smoking
Male
Age
Hypertension
Hyperlipidaemia
Connective tissue disorders: Marfan’s syndrome, Ehlers-Danlos syndrome
Inflammatory disorders: Behcet’s disease, Takayasu’s arteritis
What are the presenting symptoms of an unruptured AAA?
NO SYMPTOMS
Usually an incidental finding
May have pain in the back, abdomen, loin or groin
What are the presenting symptoms of a ruptured AAA?
Pain in the abdomen, back or loin
Pain may be sudden or severe
Syncope
Shock
What are the signs of an AAA on examination?
Pulsatile and laterally expansile mass on bimanual palpation of the abdominal aorta
Abdominal bruit
Retroperitoneal haemorrhage can cause Grey-Turner’s sign (brusing of the flanks)
What are the appropriate investigations for an AAA?
o Bloods - FBC, clotting screen, renal function and liver function
o Scans - Ultrasound, CT with contrast (shows whether an aneurysm has ruptured), MRI angiography
Define aortic dissection.
A condition where a tear in the aortic intima allows blood to surge into the aortic wall, causing a split between the inner and outer tunica media, creating a false lumen.
What are the risk factors for aortic dissection?
HYPERTENSION
Aortic atherosclerosis
Connective tissue disease (e.g. Marfan’s, Ehlers-Danlos, SLE)
Congenital cardiac abnormalities (e.g. coarctation of the aorta)
Aortitis
Iatrogenic (e.g. during angioplasty/angiography)
Trauma
Crack cocaine
What is a potential consequence of expansion of the false lumen in aortic dissection?
o obstructions of the subclavian, carotid, coeliac and renal arteries
- hypoperfusion of the target organs of these major arteries can give rise to other symptoms (e.g. carotid artery –> collapse)
What are the presenting symptoms of aortic dissection?
o MAIN SYMPTOM: sudden central ‘TEARING’ pain which may radiate to the back in between the shoulder blades - can mimic MI
- Other symptoms caused by obstruction of branches of the aorta:
- Carotid artery –> hemiparesis, dysphasia, blackout
- Coronary artery –> chest pain (angina or MI)
- Subclavian artery –> ataxia, loss of consciousness
- Anterior spinal artery –> paraplegia
- Coeliac axis –> severe abdominal pain (due to ischaemic bowel)
- Renal artery –> anuria, renal failure
What are the signs of aortic dissection on examination?
o Murmur on the back (below the left scapula), descending to the abdomen
o Hypertension
o Blood pressure difference between the two arms > 20 mm Hg
o Wide pulse pressure
o Hypotension may suggest tamponade
o Signs of Aortic Regurgitation -> high volume collapsing pulse, early diastolic murmur over aortic area
o Unequal arm pulses
o Palpable abdominal mass
What is pulsus paradoxus?
o abnormally large decrease in systolic blood pressure and pulse wave amplitude during inspiration
- may indicate: Tamponade, Pericarditis, Chronic sleep apnoea, Obstructive lung disease
What are the appropriate investigations for aortic dissection?
o Bloods - FBC, X-match 10 units of blood, U&E, clotting screen
o CXR - widened mediastinum
o ECG - often NORMAL -> if the ostia of the right coronary artery is compromised you may get signs of: left ventricular hypertrophy, inferior MI
o CT Thorax - shows false lumen
o Echocardiography
o Cardiac catheterisation and aortography
What is the diagnosis from this CT?
Stanford Type A/Ascending Aortic Dissection
What is the diagnosis from this CT?
Stanford Type B/Descending Aortic Dissection
Define aortic regurgitation.
Reflux of blood from the aorta into the left ventricle during diastole.
What are the risk factors for aortic regurgitation?
o Aortic valve leaflet abnormalities or damage -> bicuspid aortic valve, infective endocarditis, rheumatic fever, trauma
o Aortic root/ascending aorta dilatation -> systemic hypertension, aortic dissection, aortitis, arthritides (e.g. rheumatoid arthritis, seronegative arthritides), connective tissue disease (e.g. Marfan’s, Ehlers-Danlos), pseudoxanthoma elasticum, oteogenesis imperfecta
What are the symptoms of chronic aortic regurgitation?
Initially ASYMPTOMATIC
Later on, the patient may develop symptoms of heart failure (e.g. exertional dyspnoea, orthopnoea, fatigue)
What are the symptoms of severe acute aortic regurgitation?
Sudden cardiovascular collapse -> left ventricle cannot adapt to the rapid increase in end-diastolic volume
What are the signs of aortic regurgitation on examination?
Collapsing (water-hammer) pulse
Wide pulse pressure
Thrusting and heaving displaced apex beat
Early diastolic murmur over the aortic valve region - maybe an ejection systolic murmur because of increased flow across the valve
Austin Flint mid-diastolic murmur (only is severe AR) - heard over the apex due to turbulent reflux hitting the anterior cusp of the mitral valve causing a physiological mitral stenosis
What are the appropriate investigations fro aoritic regurgitation?
o CXR -> cardiomegaly, dilatation of ascending aorta, pulmonary oedema (if accompanied by left heart failure)
o ECG - > may show left ventricular hypertrophy = deep S in V1/2, tall R in V5/6, inverted T waves in lead I, aVL, V5/6, left axis deviation
o Echocardiogram -> may show underlying cause (e.g. aortic root dilatation, bicuspid aortic valve) or effects of aortic regurgitation
o Doppler echocardiogram -> show AR and indicate severity
o Cardiac catheterisation with angiography -> if uncertainty about the functional state of the ventricle or the presence of coronary artery disease
Define aortic stenosis.
Narrowing of the left ventricular outflow at the level of the aortic valve.
What are the causes of aortic stenosis?
Secondary to rheumatic heart disease (MOST COMMON WORLDWIDE)
Calcification of a congenital bicuspid aortic valve
Calcification/degeneration of a tricuspid aortic valve in the elderly
What are the presenting symptoms of aortic stenosis?
May be ASYMPTOMATIC initially
Angina (due to increased oxygen demand of the hypertrophied left ventricle)
Syncope or dizziness on exercise (due to outflow obstruction)
Symptoms of heart failure (e.g. dyspnoea, orthopnoea)
What are the signs of aortic stenosis on examination?
Narrow pulse pressure
Slow-rising pulse
Thrill in the aortic area (only if severe)
Forceful sustained thrusting undisplaced apex beat
Ejection systolic murmur at the aortic area, radiating to the carotid artery
Second heart sound may be softened or absent (due to calcification)
A bicuspid valve may produce an ejection click
What are the appropriate investigations stenosis?
o ECG -> LBBB, signs of left ventricular hypertrophy = deep S in V1/2, tall R in V5/6, inverted T waves in I, aVL and V5/6, left axis deviation
o CXR -> post-stenotic enlargement of ascending aorta, calcification of aortic valve
o Echocardiogram -> structural changes of the valves and level of stenosis, estimation of aortic valve area and pressure gradient across the valve in systole, left ventricular function
o Cardiac angiography -> differentiation from other causes of angina (e.g. MI)
What are the signs of left ventricular hypertrophy?
Deep S in V1/2
Tall R in V5/6
Inverted T waves in I, aVL and V5/6
Left axis deviation
Define arterial ulcer.
A localised area of damage and breakdown of skin due to inadequate arterial blood supply
What are the risk factors for arterial ulcers?
Coronary heart disease
History of stroke or TIA
Diabetes mellitus
Peripheral arterial disease (e.g. intermittent claudication)
Obesity and immobility
What are the presenting symptoms of an arterial ulcer?
NIGHT PAIN - hallmark of arterial ulcers -> pain is worse when supine (because arterial blood flow is further reduced when supine) -> often patients combat this by dangling the affected leg off the end of the bed
What are the signs of arterial ulcers examination?
Punched-out, elliptical appearance
Hairlessness
Pale skin
Absent pulses
Nail dystrophy
Wasting of calf muscles
Ulcer base contains grey, granulation tissue
What are the appropriate investigations for arterial ulcers?
o Duplex ultrasonography of lower limbs -> assess patency of arteries and potential for revascularisation or bypass surgery
o Anti-brachial Pressure Index (ABPI)
o Percutaneous angiography
o ECG
o Bloods -> fasting serum lipids, fasting blood glucose and HbA1c (diabetes is a major risk factor), FBC (anaemia worsens the ischaemia)
Define AF.
Rapid, chaotic and ineffective atrial electrical conduction.
What are the categories of AF?
Permanent
Persistent
Paroxysmal
What are the causes of AF?
o Systemic causes = thyrotoxicosis, hypertension, pneumonia, alcohol
o Heart causes = mitral valve disease, ischaemic heart disease, rheumatic heart disease, cardiomyopathy, pericarditis, sick sinus syndrome, atrial myxoma
o Lung causes = bronchial carcinoma, PE
o No identifiable cause
What are the presenting symptoms of AF?
Often ASYMPTOMATIC
Palpitations
Syncope (if low output)
Symptoms of the cause of AF
What are the signs of AF on examination?
Irregularly irregular pulse
Difference in apical beat and radial pulse
Check for signs of thyroid disease and valvular disease
What are the appropriate investigations for AF?
o ECG - uneven baseline with absent p waves, irregular intervals between QRS complexes
o Bloods - cardiac enzymes, TFT, lipid profile, U&Es, Mg2+ and Ca2+ (last 3 due to increased risk of digoxin toxicity with hypokalaemia, hypomagnesaemia and hypercalcaemia)
o Echocardiogram - mitral valve disease, left atrial dilatation, left ventricular dysfunction, structural abnormalities
What is treatment for AF?
o FIRST treat any REVERSIBLE causes (e.g. thyrotoxicosis, chest infection)
o Rhythm control
- if > 48 hrs since onset of AF = anti-coagulate for 3-4 weeks before attempting cardioversion
- if < 48 hrs since onset of AF = DC cardioversion (2 x 100 J, 1 x 200 J) or chemical cardioversion: flecainide or amiodarone
- prophylaxis against AF = sotalol, amiodarone, flecainide, consider pill-in-the-pocket (single dose of a cardioverting drug (e.g. flecainide) for patients with paroxysmal AF) strategy for suitable patients
o Rate control
- Chronic (Permanent) AF = control ventricular rate with digoxin, verapamil, beta-blockers and aim for ventricular rate of 90 bpm
o Stroke risk stratifcation = low risk patients = aspirin and high risk patients = warfarin (based on the CHADS-Vasc score)
What is the CHADS-Vasc Score?
- working out risk factors for a stroke
What are the possible complications of AF?
o Thromboembolism - embolic stroke risk of 4% per year and risk is increased with left atrial enlargement or left ventricular dysfunction
o Worsening of existing heart failure
Define cardiomyopathy.
Primary disease of the myocardium which can be dilated, hypertrophic or restrictive.
What is the cause of the majority of cardiomyopathies?
- idiopathic
What are the risk factors for dilated cardiomyopathy?
Post-viral myocarditis
Alcohol
Drugs (e.g. doxorubicin, cocaine)
Familial
Thyrotoxicosis
Haemochromatosis
Peripartum
What are the risk factors for hypertrophic cardiomyopathies?
- genetics -> up tp 50% are genetic
What are the risk factors for restrictive cardiomyopathies?
Amyloidosis
Sarcoidosis
Haemochromatosis
What are the presenting symptoms of dilated cardiomyopathy?
Symptoms of heart failure
Arrhythmias
Thromboembolism
Family history of sudden death
What are the presenting symptoms of hypertrophic cardiomyopathy?
Usually NO SYMPTOMS
Syncope
Angina
Arrhythmias
Family history of sudden death
What are the presenting symptoms of restrictive cardiomyopathy?
Dyspnoea
Fatigue
Arrhythmias
Ankle or abdominal swelling
Family history of sudden death
What are the signs of dilated cardiomyopathy on examiation?
Raised JVP
Displaced apex beat
Functional mitral and tricuspid regurgitations
Third heart sound
What are the signs of hypertrophic cardiomyopathy on examination?
Jerky carotid pulse
Double apex beat
Ejection systolic murmur
What are the signs of restrictive cardiomyopathy on examination?
- Raised JVP = Kussmaul Sign - paradoxical rise in JVP on inspiration due to limited ventricle filling
- Third heart sound
- Ascites
- Ankle oedema
- Hepatomegaly
What are the appropriate investigations for cardiomyopathy?
o CXR = Cardiomegaly, Heart failure
o ECG = Non-specific ST changes, Conduction defects, Arrhythmias
- Hypertrophic = left-axis deviation, signs of left ventricular hypertrophy, Q waves in inferior and lateral leads
- Restrictive = low voltage complexes
o Echocardiography
- Dilated = dilated ventricles with global hypokinesia
- Hypertrophic = ventricular hypertrophy (asymmetrical septal hypertrophy)
- Restrictive = non-dilated non-hypertrophied ventricles, atrial enlargement, preserved systolic function, diastolic dysfunction, granular or sparkling appearance of myocardium in amyloidosis
o Cardiac Catheterisation
o Endomyocardial Biopsy
o Pedigree or Genetic Analysis
Define constrictive pericarditis.
Chronic inflammation of the pericardium with thickening and scarring. It limits the ability of the heart to function normally.
What are the risk factors for constrictive pericarditis?
Idiopathic
Virus
TB
Mediastinal irradiation
Post-surgical
Connective tissue disease
Why is constrictive pericarditis underdiagnosed?
- difficult to distinguish it from restrictive cardiomyopathy and other causes of right heart failure
What are the presenting signs and symptoms of constrictive pericarditis?
o Gradual-onset of symptoms -> early symptoms and signs may be very subtle whereas advanced would be jaundice, cachexia, muscle wasting
o Right Heart Failure Signs = dyspnoea, peripheral oedema, raised JVP, Kussmaul’s sign (paradoxical rise in JVP on inspiration), pulsatile hepatomegaly
What are the appropriate investigations for constrictive pericarditis?
o CXR - may show calcification of the pericardium
o Echocardiogram - usually diagnostic and helps distinguish from restrictive cardiomyopathy
o MRI/CT - allows assessment of thickness of pericardium
o Pericardial biopsy - may be indicated (especially if suspected infective cause)
Define DVT?
Formation of a thrombus within the deep veins (most commonly in the calf or thigh).
What are the risk factors for DVT’s?
Combined oral contraceptive pill
Post-surgery
Prolonged immobility
Obesity
Pregnancy
Dehydration
Smoking
Polycythaemia
Thrombophilia (e.g. protein C deficiency)
Malignancy
What are the presenting symptoms of a DVT?
- swollen limb
- often painless
What are the signs of DVT’s on examination?
o Local erythema, warmth and swelling
o Measure the leg circumference
o Varicosities (swollen/tortuous vessels)
o Skin colour changes
o Homan’s Sign - forced passive dorsiflexion of the ankle causes deep calf pain
What should be carried out if there is a suspected DVT?
o Wells Score -> score >2 = high risk of a PE
o examine for a PE - RR, sats, HR
What are the appropriate investigations for a DVT?
o Doppler Ultrasound = GOLD STANDARD
o Impedance Plethysmography - changes in blood volume results in changes of electrical resistance
o Bloods - D-dimer, thrombophilia screen if indicated
o If PE suspected = ECG, CXR, ABG
What is the treatment plan for a DVT?
o Anti-coagulation - heparin whilst waiting for warfarin to increase INR to the target range of 2-3 -> if not extended above the knee anticoagulated for 3 months but if they do it is 6 months
- recurrent DVTs require long-term warfarin
o IVC filter - may be used if anticoagulation is contraindicated and there is a risk of embolisation
o Prevention - graduated compression stockings, mobilisation, prophylactic heparin (if high risk e.g. hospitalised patients)
What are the possible complications of DVT’s?
- PE
- Venous infarction (phlegmasia cerulea dolens)
- Thrombophlebitis (results from recurrent DVT)
- Chronic venous insufficiency
Define gangrene.
Tissue necrosis, either wet with superimposed infection, dry or gas gangrene.
Define necrotising fasciitis.
A life-threatening infection that spreads rapidly across fascial planes.
What are the risk factors for gangrene/necrotising fasciitis?
Diabetes
Peripheral vascular disease
Obesity
Leg ulcers
Malignancy
Immunosuppression/Steroid use
Puncture/surgical wounds
What are the presenting symptoms of gangrene?
Pain
Discolouration of affected area
Often affects extremities or areas subject to high pressure
What are the presenting symptoms of necrotising fasciitis?
Pain - often seems SEVERE and out of proportion to the apparent physical signs
Predisposing event (e.g. trauma, ulcer, surgery)
What are the signs of gangrene on examination?
o Painful area = erythematous region around gangrenous tissue
o Gangrenous tissue = black because of haemoglobin break down products
o Wet Gangrene - tissue becomes boggy with associated pus and a strong odour caused by the activity of anaerobes
o Gas Gangrene - spreading infection and destruction of tissues causes overlying oedema, discolouration and crepitus (due to gas formation by the infection)
What are the signs of necrotising fasciitis on examination?
o Area of erythema and oedema
o Haemorrhagic blisters may be present
o Signs of systemic inflammatory response and sepsis (high/low temperature, tachypnoea, hypotension)
What are the appropriate investigations for gangrene and necrotising fasciitis?
o Bloods - FBC, U&Es, glucose, CRP and blood culture
o Wound Swab, Pus/Fluid Aspirate - MC&S
o X-ray of affected area - may show gas produced in gas gangrene
Define 1st degree AV block.
Prolonged conduction through the AV node.
Define 2nd degree AV block, Mobitz type I.
Progressive prolongation of AV node conduction culminating in one atrial impulse failing to be conducted through the AV node, before the cycle starts again.
Define 2nd degree AV block, Mobitz type II.
Intermittent or regular failure of conduction through the AV node.
- also defined by the number of normal conductions per failed or abnormal one (e.g. 2:1 or 3:1)
Define 3rd degree/complete AV block.
No relationship between atrial and ventricular contraction. Failure of conduction through the AV node leads to ventricular contraction generated by a focus of depolarisation within the ventricle.
What are the presnting symptoms of 1st degree heart block?
- asymptomatic
What are the presenting symptoms of 2nd degree heart block, Mobitz type II?
- usually asymptomatic
What are the presenting symptoms of 2nd degree heart block, Mobitz type II and complete?
o may cause Stokes-Adams Attacks (syncope caused by ventricular asystole)
o may also cause dizziness, palpitations, chest pain and heart failure
What are the signs of heart block on examination?
o Often Normal
o Check for signs of a potential cause of heart block
o Complete Heart Block = slow large volume pulse, JVP may show cannon a waves, signs of reduced cardiac output (e.g. hypotension, heart failure)
What are the appropriate investigations for heart block?
o ECG - GOLD STANDARD
- First degree = fixed prolonged PR interval (> 0.2 s)
- Mobitz type I = progressively prolonged PR interval, culminating in a P wave that is NOT followed by a QRS complex.
- Mobitz type II = intermittently a P wave is NOT followed by a QRS. with a possible pattern (e.g. 2:1 or 3:1)
- Complete heart block = no relationship between P waves and QRS complexes. If QRS is initiated in the: Bundle of His = narrow complex or more distally = wide complex and slow rate (~ 30 bpm)
o CXR - cardiac enlargement, pulmonary oedema
o Bloods - TFTs, digoxin level, cardiac enzymes, troponin
o Echocardiogram - wall motion abnormalities, aortic valve disease, vegetations
What is the treatment for heart block?
o Chronic block = Permanent pacemaker is recommended in complete heart block, advanced Mobitz type II, symptomatic Mobitz type I
o Acute Block = if associated with clinical deterioration use IV atropine and consider temporary (external) pacemaker
What are the possible complications of heart block?
Asystole
Cardiac arrest
Heart failure
Complications of any pacemaker inserted
Define hypertension.
Systolic > 140 mm Hg and/or diastolic > 90 mm Hg measured on three separate occasions.
Define malignant hypertension.
BP > 200/130 mm Hg
What are the causes of hypertension?
o Primary = .90% of cases
- essential or idiopathic hypertension
o Secondary
- Renal = renal artery stenosis, chronic glomerulonephritis, chronic pyelonephritis, polycystic kidney disease, chronic renal failure
- Endocrine = diabetes mellitus, hyperthyroidism, Cushing’s syndrome, Conn’s syndrome, hyperparathyroidism, phaeochromocytoma, congenital adrenal hyperplasia, acromegaly
- Cardiovascular = coarctation of the aorta, increased intravascular volume
- Drugs = sympathomimetics, corticosteroids, COCP
- Pregnancy = pre-eclampsia